Examining the association of vaccine-related mindsets and post-vaccination antibody response, side effects, and affective outcomes.

Background: Although vaccines are largely effective and safe, there is variability in post-vaccination experience regarding antibody response, side effects, and affective outcomes. Vaccine mindsets, specific beliefs about the vaccine, may be associated with post-vaccination experience. This is important since mindsets are malleable and may help decrease vaccine hesitancy and improve post-vaccination experience.

Methods: In a prospective study, we measured overall positive vaccine mindset and specific mindsets regarding efficacy, body response, and side effects. We tested whether vaccine mindsets before vaccination predicted neutralizing antibody response, side effects, vaccine-related stress, and affective outcomes (general stress, sadness, and happiness). Antibody response was assessed one month and six months after participants completed a SARS-CoV-2 vaccination series. Side effect experience and affective reactions were assessed daily on the vaccination day and the subsequent five days.

Results: There was no significant association between the aggregate vaccine mindset score and neutralizing antibody response; however, people with a more positive vaccine mindset reported fewer side effects, less same-day vaccine-related anxiety, and improved affective outcomes after vaccination. In secondary analyses, when specific mindsets were explored, the mindset that vaccine side effects are a sign of treatment efficacy predicted higher antibodies, but not side effects experience and vaccine-related anxiety. Vaccine efficacy and body-response mindsets predicted fewer side effects, vaccine-related anxiety, and improved affective outcomes after vaccination.

Conclusion: These findings underscore the potential of vaccine mindsets in enhancing the overall post-vaccination experience and, in some cases, increasing antibody response.